HaLeiVi -“it must be a negative statement. That is obviously the opposite intention of that Gemara, though.”
I agree that it’s not the Posheh Pshat. My Chiddush is when you do something L’shem Shomayim it could turn out bad.
The Soton meant well and it turned out bad; Penina meant well and it turned out bad. Why does the Gemmora care what the Sotton does & why? To teach you that even the Sotton acts L’shem Shomayim, but it doesn’t mean good comes out of it.